The desirability of providing a house trailer which can be used on land, and which can be converted into a houseboat for use on the water has been apparent for many years. There have been numerous proposals for providing house trailers with some form of pontoons or floats, which may be attached beneath the main structure, so that it will float on the water. However, such earlier proposals have for the most part simply been interesting paper proposals, which have been totally impracticable either from the manufacturing point of view, or alternatively from the user's point of view.
For example the storage of the floats, when the house trailer is used on land has been proposed in a variety of locations around the structure, with a variety of different forms of linkages for securing the floats beneath the main structure.
In the majority of cases, such proposals were excessively complex to manufacture, and were inherently liable to failure especially when used on the water, due to the instability of the float mounting. In addition, the operation of the mechanism to move the floats from one position to another was excessively complicated and difficult so that the actual user would find that the entire operation was probably more trouble than it was worth.